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Communication For Initializing Impossible

Detecting condition: 

Defective harness connector

Trouble symptom: 

Communication is impossible between VDC and Subaru Select Monitor.

Wiring diagram  :

Vehicle dynamics control system Ref. to WIRING SYSTEM (CROSSTREK MODEL)>VEHICLE DYNAMICS CONTROL SYSTEM .

G11257674Courtesy of SUBARU OF AMERICA, INC.
G12400307Courtesy of SUBARU OF AMERICA, INC.
G12400308Courtesy of SUBARU OF AMERICA, INC.
  1. CHECK IGNITION SWITCH  .

    Is the ignition switch ON?

    Yes:  Go to  2.

    No:  Turn the ignition switch to ON, and select Brake Control using the Subaru Select Monitor.

  2. CHECK BATTERY  .
    1. Turn the ignition switch to OFF.
    2. Measure the battery voltage.

    Is the voltage 11 V or more?

    Yes:  Go to  3.

    No:  Charge or replace the battery.

  3. CHECK BATTERY TERMINAL  .

    Is there poor contact at battery terminal?

    Yes:  Replace or tighten the battery terminal.

    No:  Go to  4.

  4. CHECK INSTALLATION OF VDC CONTROL MODULE & H/U CONNECTOR  .

    Turn the ignition switch to OFF.

    Is the VDC CONTROL MODULE & H/U connector inserted into VDC CONTROL MODULE & H/U until the clamp locks onto it?

    Yes:  Go to  5.

    No:  Insert VDC CONTROL MODULE & H/U connector into VDC CONTROL MODULE & H/U.

  5. CHECK LAN SYSTEM  .

    Perform the diagnosis for LAN system using the Subaru Select Monitor. Ref. to LAN SYSTEM (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE .

    Is DTC of CAN communication displayed?

    Yes:  Perform the diagnosis according to DTC. Ref. to LAN SYSTEM (DIAGNOSTICS)>Diagnostic Trouble Code (DTC)>LIST .

    No:  Go to  6.

  6. CHECK SUBARU SELECT MONITOR COMMUNICATION  .
    1. Turn the ignition switch to ON.
    2. Check whether communication to VDC system can be executed normally.

    Is the [Select Function] screen displayed?

    Yes:  Check the DTC in VDC system. Ref. to BRAKE CONTROL (DIAGNOSTICS)>DIAGNOSTIC TROUBLE CODE (DTC) .

    No:  Go to  7.

  7. CHECK SUBARU SELECT MONITOR COMMUNICATION  .

    Connect the Subaru Select Monitor to another vehicle to check whether the communication for initializing can be executed normally.

    Does the Subaru Select Monitor communicate normally?

    Yes:  Go to  8.

    No:  Repair or replace the Subaru Select Monitor.

  8. CHECK POWER SUPPLY CIRCUIT  .
    1. Turn the ignition switch to ON. (Engine OFF)
    2. Measure the ignition power supply voltage between VDC CONTROL MODULE & H/U connector and chassis ground.

      Connector & terminal

      (B310) No. 1 (+)-Chassis ground (-):

      (B310) No. 6 (+)-Chassis ground (-):

      (B310) No. 25 (+)-Chassis ground (-):

    Is the voltage 10-15 V?

    Yes:  Go to  9.

    No:  Repair open circuit in harness between VDC CONTROL MODULE & H/U and battery.

  9. CHECK HARNESS CONNECTOR BETWEEN VDC CONTROL MODULE & H/U AND CHASSIS GROUND  .
    1. Turn the ignition switch to OFF.
    2. Disconnect the connector from the VDC CONTROL MODULE & H/U.
    3. Measure the resistance of harness between VDC CONTROL MODULE & H/U connector and chassis ground.

      Connector & terminal

      (B310) No. 13-Chassis ground:

    Is the resistance less than 10 Ω?

    Yes:  Go to  10.

    No:  Repair the open circuit of VDC CONTROL MODULE & H/U ground circuit and poor contact of connector.

  10. CHECK POOR CONTACT OF CONNECTOR  .

    Is there poor contact of control module power supply, ground circuit and data link connector?

    Yes:  Repair the connector.

    No:  Replace the VDC CONTROL MODULE & H/U. Ref. to VEHICLE DYNAMICS CONTROL (VDC)>VDC CONTROL MODULE AND HYDRAULIC CONTROL UNIT (VDC CONTROL MODULE & H/U) .